1. Field of the Invention
The present invention relates to an image transmission apparatus of a facsimile apparatus for sending image data to a designated destination.
2. Description of the Related Art
In recent years, in a facsimile apparatus, in addition to the G3—facsimile utilizing public line, a network facsimile such as an IP (Internet Protocol)—facsimile for transmitting and receiving image data via the Internet has become popular. In the network facsimile, since large quantity of image data can be transmitted through the network facsimile in a high speed with low cost, there is an apparatus, which is capable of transmitting and receiving color images.
Due to the appearance of a color facsimile apparatus, the situation where monochrome facsimile apparatuses and color facsimile apparatuses exist together has appeared. Thus, when using a broadcast function, which is a function for transmitting the same image data to a plurality of destinations with one operation, the possibility that a color facsimile apparatus and a monochrome facsimile apparatus coexist in broadcast destinations occur. In order to appropriately conduct a transmission process, various technologies have been proposed.
For example, Japanese Patent Application open to Public Inspection No. 2005-26978 discloses an Internet facsimile apparatus, which is arranged to read a document in color, to separate the destinations into a color machine group and a monochrome group, to send the read image data to the color machine group as it is and to conduct a color/monochrome conversion before sending the image data to the monochrome group, when a color machine and a monochrome machine coexist in the broadcast destinations and at the same time a color transmission is specified as a transmission mode.
As described above, when conducting the color/monochrome conversion before sending the image, which has been read in color, to the monochrome machine, if a CPU (Central Processing Unit) of the facsimile apparatus conducts the conversion, the processing load of the CPU becomes heavy. Thus, it interferes with the proceedings of the other process and the performance as an apparatus drops down. For example, when receiving a next job reservation operation while conducting the color/monochrome process, hindrances occur that the responses to the operation of the user becomes slow.
FIG. 4 illustrates a conventional mixed broadcast transmission process. According to the conventional process, the CPU reads a document in a color mode (a step S201) and checks whether there is a destination, to which the document needs to be sent in a monochrome mode, in the broadcast destinations (a step S202). When a monochrome exclusive destination coexists with a destination to which the image can be sent in a color mode (the step S202; Y), the image data, which has been read in the color mode, is converted into monochrome image data (color/monochrome conversion) to generate monochrome image data (a step S203).
Then, color image data is transmitted to the destination, which is capable of receiving the color image data (a step S204), monochrome data is transmitted to the monochrome exclusive destination and the process finishes (END). When no monochrome exclusive destination coexists with the destination to which the image can be sent in a color mode (the step S202; N), the CPU transmits the color image data to all the destinations of the broadcast transmission (a step S205) and finishes the process (END). As described above, according to the conventional process, color/monochrome conversion is necessary. Accordingly, there are problems associated with the conventional process that the processing load of the CPU increases due to the color/monochrome conversion and hardware dedicated to the conversion is necessary.
On the other hand, when installing the hardware dedicated to the color/monochrome conversion into the apparatus, the load of the CPU can be reduced. However, it increases the cost of the apparatus. Accordingly, it is difficult to apply the hardware to a less expensive apparatus.
To conduct reading operation of the same document in the color mode and in the monochrome mode twice increases a reading time and makes the operation complicated. Further, since a subtle change of the reading position of the same document makes a document as if which were a different document, it is not preferable to conduct reading operation of the same document twice.
Therefore, it is an object to solve the problems described above to provide an image transmission apparatus, which is capable of conducting broadcast transmission without conducting color/monochrome conversion of image data and without reading operation twice against the same document even when a monochrome exclusive destination (a monochrome destination) coexists with a destination to which the image can be sent in a color mode (a color destination) in the broadcast destinations.